Hadrian: The Emperor Who Drew the Lines
Hadrian spent more time away from Rome than any emperor before or after him. In twenty-one years of rule, from 117 to 138 AD, he made two extended tours of the empire’s provinces, personally inspecting frontiers, reviewing troops, visiting cities, correcting administrative abuses, and leaving behind a physical record of his passage in the form of temples, baths, aqueducts, and the walls and frontier fortifications whose most famous example still bears his name. He was the most traveled of emperors, the most architecturally prolific, and the most systematically interested in the practical realities of governance at the provincial level. He was also the most controversial figure of the Antonine dynasty, for reasons that have as much to do with his personality as with his policies.
He came to power in 117 AD under circumstances sufficiently ambiguous that the questions were never fully resolved. Trajan died in Cilicia without designating a public successor; the adoption of Hadrian was announced by Trajan’s wife Plotina, who was known to favor him, from the emperor’s deathbed in a manner that Hadrian’s opponents suspected was backdated or fabricated. Whether the adoption was genuine or engineered, Hadrian was accepted by the Senate and the armies, which was the only acceptance that mattered operationally. His first significant act — the abandonment of Trajan’s Mesopotamian conquests, withdrawing Roman forces from the most distant territorial gains Trajan had achieved — generated immediate hostility from a senatorial class that interpreted it as weakness. Hadrian interpreted it as strategic realism: the extended eastern frontier was indefensible at the cost required.
The four senators executed early in his reign — for alleged conspiracy, though Hadrian denied ordering the executions and blamed the Senate’s own initiative — attached a shadow to his early rule that never fully lifted. The relationship between Hadrian and the Senate was formally correct and substantively hostile for most of his reign, a mutual suspicion that expressed itself in the senatorial literary tradition’s ambivalent portrait of him: an emperor of genuine ability and wide-ranging cultural achievement whom the senatorial class found arrogant, capricious, and difficult to trust.
His architectural program was the most ambitious since Augustus. In Rome, he completed the Temple of Venus and Roma — designed by himself, a point of professional pride that led to a famous quarrel with the architect Apollodorus of Damascus, who had designed Trajan’s forum and who reportedly criticized Hadrian’s design in terms that cost him first his career and then his life. He rebuilt the Pantheon in its current form. He built the vast complex at Tivoli — the Villa Adriana — whose scale, diversity of architectural spaces, and deliberate evocation of places he had visited across the empire make it the most personal imperial building project in Roman history, a physical diary of a man who was everywhere and reproduced what he found in his private retreat. The mausoleum he built for himself across the Tiber — now the Castel Sant’Angelo — was completed and used for his burial and later served as papal fortress and prison for a millennium and a half.
The frontier policy that bears his most visible legacy was the construction of physical demarcations along the empire’s borders. Hadrian’s Wall in Britain, begun in 122 AD during his provincial tour, was the most elaborate: a continuous stone wall running eighty Roman miles across northern Britain, with forts, milecastles, and turrets at regular intervals, flanked by a military road and a further earthwork ditch to the south. Similar structures were built along the German frontier and in North Africa. The strategic logic was explicit: define the empire’s limits, invest in the infrastructure to monitor and control movement across those limits, and abandon the Trajanic ambition of continuous expansion in favor of consolidated defense of existing territory. It was a doctrine of sufficiency rather than ambition, and it shaped Roman strategic thinking for the following century.
His relationship with the young Greek Antinous, who drowned in the Nile in 130 AD, is among the most extensively documented personal relationships of any Roman emperor and the most openly expressed grief in the imperial record. Hadrian founded a city — Antinoopolis — at the site of the drowning, instituted religious honors, and commissioned a proliferation of portraits and statues that spread Antinous’s image across the empire in numbers that survive into the present day. The ancient sources describe the mourning as excessive by Roman standards, which themselves permitted considerable public grief; modern historians debate whether the relationship was sexual, emotionally intimate without being physical, or politically significant in some way that the personal framing obscures. What is certain is that it was important enough to Hadrian to generate an unprecedented imperial response, and that this response tells us something about a man who throughout his reign demonstrated an unusual willingness to act on personal conviction despite institutional expectation.
He died in 138 AD at his villa at Baiae on the Bay of Naples, having spent his last years in declining health and considerable political difficulty. He had designated a succession he was unsatisfied with and revised it — adopting Antoninus Pius on the condition that Antoninus in turn adopt Marcus Aurelius and Lucius Verus — producing the chain of adoption that governed the following half-century. The Senate voted against his deification after his death; Antoninus Pius insisted on it as the condition for his own cooperation, which gave the next dynasty its cognomen: Pius, the dutiful son. Hadrian’s walls still stand. His relationship with the institution that outlasted him was, to the end, a negotiation.